"Last week I communicated to Senator Obama and his presidential campaign my firm intention to remain in the United States Senate, where I believe I am best equipped to serve the people of Virginia and this country," Webb said in an issued statement. “Under no circumstances will I be a candidate for Vice President."

Webb, a moderate Democrat and Vietnam veteran who successfully unseated former Virginia Sen. George Allen in 2006, has often been mentioned as a potential VP choice given his likely appeal in more conservative states, his early opposition to the Iraq war, and his credibility with military issues.

The Virginia senator also co-sponsored the Senate G.I. benefits bill passed this spring that seeks to increase tuition reimbursements for veterans. Despite an initial veto threat, President Bush signed the bill into law last week.

"I entered elective politics because of my commitment to strengthen America's national security posture, to promote economic fairness, and to increase government accountability," Webb also said. "I have worked hard to deliver upon that commitment, and I am convinced that my efforts and talents toward those ends are best served in the Senate."

Webb did not endorse a Democratic candidate during the primary season. Fellow Virginians Tim Kaine, the state’s governor, and Mark Warner, a former governor who is currently running for Senate, were also considered to be on in contention for the VP slot. Warner also took himself out of the running last month.